The overall objectives of our research are to define further thhe mechanisms of gastric acid secretion and hormone release in normal human subjects, to evaluate abnormalities of gastric function and gastrin release in patients with peptic ulcer, to develop and study methods for reducing acid secretion in patients with acid-peptic disease, to develop and study methods for reducing acid secretion in patients with acid-peptic disease, to develop new methods of diagnosing and treating patients with Zolligner-Ellison syndrome, and to study abnormalitites in gastric function in patients with diabetes mellitus. During the coming year we plan to study the effect of opiate antagonists on acid secretion and serum gastrin and pancreatic polypeptide concentration, to evaluate increased vagal tone as a cause of basal hypersecretion in ulcer patients, to study the effect of vagal mechanisms on gastrin release, to study combinations of antisecretory drugs and new histamine H2-receptor antagonists, and to study new methods of treating Zollinger-Ellison syndrome.